There is evidence that the toxic and carcinogenic nature of certain aromatic hydrocarbons may be linked to their initial conversion to reactive epoxides. It is now thought that the ultimate carcinogens responsible for the carcinogenic nature of benzo(a)pyrene, a widely-spread environmental carcinogen, are 7,8-diol-9,10-epoxide metabolites. A knowledge of the chemical mechanisms whereby such highly reactive epoxides undergo enzymic and non-enzymic (including hydrolysis) reactions therefore become very important. The goal of this research is to carry out a kinetic investigation of the catalytic and non-catalytic reactions of epoxides that are either carcinogenic, or related in sttucture to carcinogenic epoxides, in aqueous media. The kinetic data, along with product analyses, will be essential to the understanding of the mechanisms of hydrolysis and other competing reactions that such epoxides undergo. A knowledge of the mechanisms of non-enzyme-catalyzed reactions of these epoxides will be most helpful and may provide some insight in understanding the mechanisms involved in their reactions with biological molecules.